Prior art film-head fabrication required a process of chemical etching of sputtered dielectric or nonmagnetic material to open the back gap region. End-point detection during the etching was very difficult to determine at best. Over-etching could result in attack on the underlying magnetic layer. Under-etching leaves a residual layer in the back gap which adversely effects the efficiency of the magnetic transducer by preventing intimate contact of the magnetic layers.
The prior art references do not address the problem of creating on a single substrate, a separate thin film as a (1.) read head and write head; (2.) read/write head and servo head; or, (3.) read head and write/servo head. The prior art has not achieved this type of fabrication through process of lift-off of material and, therefore, the prior art processes, while broadly touching on etching and lift-off processes, do not show the technique as now disclosed.